Multifunctional display and operating devices are used more and more these days in motor vehicles. On the one hand, they are used for displaying information on the state of the motor vehicle. On the other hand, these multifunctional display and operating devices are used to control vehicle systems, such as a navigational system or an automobile radio. A fixed function may be assigned to the individual operating elements. However, in certain conventional arrangements, multifunctional display and operating devices are preferred in which information is shown in the display field which indicate functional directions to the individual operating elements. This is done, for example, by showing the individual assigned functions on the display field, next to the operating elements. In other arrangements, the positioning of the functions on the display field correspond to the positioning of the operating elements of the multifunctional display and operating device. Such a multifunctional display and operating device is described, for example, in PCT International Published Patent Application No. WO 00/21795.
In certain conventional the multifunctional display and operating devices, the operating elements are designed as stroke keys. When operating these stroke keys, an up-and-down movement is executed perpendicular to the operating plane of the keys. In order to ensure a reliable and sure method of functioning of such stroke keys, it is necessary to provide relatively large gap dimensions between a stroke key and a panel or guiding device surrounding it. Operating elements that are arranged adjacently also have to maintain certain gap dimensions, so as to prevent that, when a key is operated, another key is operated along with it. However, in order to accommodate as large as possible a number of operating elements on a surface of a multifunctional display and operating device, it would be desirable to keep the gap clearances to as small as possible. If the distances between the gaps are selected to be too slight, when the up-and-down motions of the keys are executed, the keys may become skewed or jammed.
In order also to make possible operation in the dark, it is preferred that the operating elements be illuminated from the rear of the operating plane. When doing this, it is desirable to illuminate as large an area of the operating surface as possible. In order to attain a sure guidance of the keys, however, guideways are provided on the side of the key facing away from the operating surface which, in particular in the case of small keys, enclose a large part of the side facing away from the operating surface such that, in the case of stroke keys whose size is about 2 cm×1.2 cm, only a range of approximately 50% of the operating surface is able to be illuminated.
In particular in the case of stroke keys having a large planar extension or (and) a slight lift, in order to achieve a reliable switching response, it is mostly necessary to use several switching elements or a switching element that includes several switching devices that are spatially separated from one another (for example, switching domes arranged in switch mats). The reason is that otherwise, in response to an operating force that is not impinging centrally on the stroke key, skewing of the stroke key may take place and the reliable triggering of a switching process is not securely ensured in response to each operation. It is desirable to save on switching elements or switching devices without having to put up with a limitation in switching reliability.